Wind turbines or wind power plants comprise a drive train, which extends from the rotor or rotor hub to the generator. The drive train can comprise a hub, a rotor shaft (or main shaft) a gearbox input shaft, a gearbox and a generator. The drive train is mainly configured to transfer torque from the rotor to the generator. However, there are also other rotor loads different than the mere torque load. These other loads should be transferred to and eliminated by the nacelle structure. The load path of these other loads through the drive train to the nacelle structure depends on the particular arrangement and on variations and magnitudes of these loads, the machining tolerances, load deformations, thermal effects and other conditions. All this may result in undesirable parasitic forces that have the potential to damage elements in the drive train, particularly the gearbox components and the main bearings. Eliminating these parasitic forces is inseparably connected with gearbox and bearing reliability.
WO 2012/052022 A1 discloses a drive train for a wind turbine comprising a main shaft and a gearbox with a gearbox input shaft driven by the main shaft. There are two couplings located between the main shaft and the gearbox input member of the gearbox. The two couplings are configured such that the transmission of undesired loads is reduced.
WO 2013/007322 A1 discloses a drive train comprising a rotor shaft and a generator input shaft which are coupled with each other via a coupling having elastic elements. It is disclosed that the coupling comprises two coupling parts which are rigidly connected with the rotor shaft and the generator shaft. However, the elastic elements provided between the coupling parts have chambers filled with a fluid, in particular a hydraulic fluid and they are arranged in pairs.